Streams and consciousness: visual awareness and the brain

Vision is our most powerful sense and, arguably, it gives us our most vivid sensory and imaginal experiences. It is also one of the best understood systems in contemporary neuroscience. Yet, contrary to both traditional assumptions and our phenomenological intuition, recent research has shown that vision is not a monolithic system that creates a single general-purpose representation in the brain. For example, selective brain damage can compromise visuomotor control while leaving perception intact, and damage elsewhere can compromise visual perception while leaving visuomotor control intact. Thus, it is becoming apparent that we have two (largely) separate visual systems. One of them is dedicated to the rapid and accurate guidance of our movements: it is a complex and powerful system, and yet it lies outside the realm of our conscious visual awareness. The other seems to provide our perceptual phenomenology, although its primary purpose is probably to provide suitably coded visual inputs for storage in and retrieval from memory. According to this conceptualization, both systems can be seen as serving our behaviour, but each does so on a different time scale. Recent studies suggest that neuropsychological research in humans can play a central role in bridging the gap between neurobiological studies of the monkey's visual system and the search to narrow down the brain mechanisms that mediate our visual awareness.     

The Transcendent Function: The Numinosum in Gene Expression,Neurogenesis, and Healing

The process of coming to terms with the unconscious is a true labor, a work which involves both action and suffering. It has been named the “transcendent function” because it represents a function based on real and “imaginary,” or rational and irrational, data, thus bridging the yawning gulf between conscious and unconscious. It is a natural process, a manifestation of the energy that springs from the tension of opposites, and it consists in a series of fantasy-occurrences which appear spontaneously in dreams and visions, (p. 80) —C. G. Jung, 1943/1966     

Teresa of Avila: The will and the weaving

For more than forty-five years as a Carmelite nun in the sixteenth century, Teresa of Avila suffered from great physical pain. We see in her life how disciplined prayer can become a healing experience that moves from minimal psychic representation to full symbolic representation. After a brief examination of Teresa's life, two theoretical perspectives on somatic manifestation will be reviewed: the theory of conversion hysteria of the classical Freudian school, and the differentiation Joyce McDougall draws between hysterical and psychosomatic phenomena. For the psychosomatic, as the mystic, the void of wordless space has significance. Following after McDougall on the suffering body, a third perspective will be offered: the concept of conscious body suffering as a means to inner change.     

Attention and consciousness: two distinct brain processes

The close relationship between attention and consciousness has led many scholars to conflate these processes. This article summarizes psychophysical evidence, arguing that top-down attention and consciousness are distinct phenomena that need not occur together and that can be manipulated using distinct paradigms. Subjects can become conscious of an isolated object or the gist of a scene despite the near absence of top-down attention; conversely, subjects can attend to perceptually invisible objects. Furthermore, top-down attention and consciousness can have opposing effects. Such dissociations are easier to understand when the different functions of these two processes are considered. Untangling their tight relationship is necessary for the scientific elucidation of consciousness and its material substrate.     

The dreaming brain/mind, consciousness and psychosis

Several independent lines of research in neurobiology seem to support the phenomenologically-grounded view of the dreaming brain/mind as a useful model for psychosis. Hallucinatory phenomena and thought disorders found in psychosis share several peculiarities with dreaming, where internally generated, vivid sensorimotor imagery along with often heightened and incongruous emotion are paired with a decrease in ego functions which ultimately leads to a severe impairment in reality testing. Contemporary conceptualizations of severe mental disorders view psychosis as one psychopathological dimension that may be found across several diagnostic categories. Some experimental data have shown cognitive bizarreness to be equally elevated in dreams and in the waking cognition of acutely psychotic subjects and in patients treated with pro-dopaminergic drugs, independent of the underlying disorder. Further studies into the neurofunctional underpinnings of both conditions will help to clarify the use and validity of this model.     

The link between brain learning, attention, and consciousness

The processes whereby our brains continue to learn about a changing world in a stable fashion throughout life are proposed to lead to conscious experiences. These processes include the learning of top-down expectations, the matching of these expectations against bottom-up data, the focusing of attention upon the expected clusters of information, and the development of resonant states between bottom-up and top-down processes as they reach an attentive consensus between what is expected and what is there in the outside world. It is suggested that all conscious states in the brain are resonant states and that these resonant states trigger learning of sensory and cognitive representations. The models which summarize these concepts are therefore called Adaptive Resonance Theory, or ART, models. Psychophysical and neurobiological data in support of ART are presented from early vision, visual object recognition, auditory streaming, variable-rate speech perception, somatosensory perception, and cognitive-emotional interactions, among others. It is noted that ART mechanisms seem to be operative at all levels of the visual system, and it is proposed how these mechanisms are realized by known laminar circuits of visual cortex. It is predicted that the same circuit realization of ART mechanisms will be found in the laminar circuits of all sensory and cognitive neocortex. Concepts and data are summarized concerning how some visual percepts may be visibly, or modally, perceived, whereas amodal percepts may be consciously recognized even though they are perceptually invisible. It is also suggested that sensory and cognitive processing in the What processing stream of the brain obey top-down matching and learning laws that are often complementary to those used for spatial and motor processing in the brain's Where processing stream. This enables our sensory and cognitive representations to maintain their stability as we learn more about the world, while allowing spatial and motor representations to forget learned maps and gains that are no longer appropriate as our bodies develop and grow from infanthood to adulthood. Procedural memories are proposed to be unconscious because the inhibitory matching process that supports these spatial and motor processes cannot lead to resonance.     

The consciousness of surrender and the surrendered consciousness: ecstatic dreams of Lord Krishna

This article is based on research at Bhaktivedanta Manor, the main UK centre of the Hare Krishna movement, and it examines ecstatic dreams of Lord Krishna which devotees at the Manor claim to experience. With a focus on one key informant's account of such dreams, the article explores the role the dreams play in spiritual and devotional life. Moving away from psychoanalytic and from similar or related psychological interpretations of spiritual dreams, it advances an alternative approach, a phenomenologically oriented approach rooted in the work of the French philosopher Jean‐Paul Sartre. The article further contends that this provides students and scholars of spiritual dreams with a helpful model, not merely for analysing accounts of ecstatic dreams reported by members of the Hare Krishna movement, but also, perhaps, for interpreting spiritual or ecstatic dreams reported by adherents of other faiths.     

The brain basis of a "consciousness monitor": scientific and medical significance.

Surgical patients under anesthesia can wake up unpredictably and be exposed to intense, traumatic pain. Current medical techniques cannot maintain depth of anesthesia at a perfectly stable and safe level; the depth of unconsciousness may change from moment to moment. Without an effective consciousness monitor anesthesiologists may not be able to adjust dosages in time to protect patients from pain. An estimated 40,000 to 200,000 midoperative awakenings may occur in the United States annually. E. R. John and coauthors present the scientific basis of a practical "consciousness monitor" in two articles. One article is empirical and shows widespread and consistent electrical field changes across subjects and anesthetic agents as soon as consciousness is lost; these changes reverse when consciousness is regained afterward. These findings form the basis of a surgical consciousness monitor that recently received approval from the U.S. Food and Drug Administration. This may be the first practical application of research on the brain basis of consciousness. The other John article suggests theoretical explanations at three levels, a neurophysiological account of anesthesia, a neural dynamic account of conscious and unconscious states, and an integrative field theory. Of these, the neurophysiology is the best understood. Neural dynamics is evolving rapidly, with several alternative points of view. The field theory sketched here is the most novel and controversial.     

Measuring consciousness in dreams: The lucidity and consciousness in dreams scale

In this article, we present results from an interdisciplinary research project aimed at assessing consciousness in dreams. For this purpose, we compared lucid dreams with normal non-lucid dreams from REM sleep. Both lucid and non-lucid dreams are an important contrast condition for theories of waking consciousness, giving valuable insights into the structure of conscious experience and its neural correlates during sleep. However, the precise differences between lucid and non-lucid dreams remain poorly understood. The construction of the Lucidity and Consciousness in Dreams scale (LuCiD) was based on theoretical considerations and empirical observations. Exploratory factor analysis of the data from the first survey identified eight factors that were validated in a second survey using confirmatory factor analysis: INSIGHT, CONTROL, THOUGHT, REALISM, MEMORY, DISSOCIATION, NEGATIVE EMOTION, and POSITIVE EMOTION. While all factors are involved in dream consciousness, realism and negative emotion do not differentiate between lucid and non-lucid dreams, suggesting that lucid insight is separable from both bizarreness in dreams and a change in the subjectively experienced realism of the dream.     

The unity of consciousness: subjects and objectivity

This paper concerns the role that reference to subjects of experience can play in individuating streams of consciousness, and the relationship between the subjective and the objective structure of consciousness. A critique of Tim Bayne’s recent book indicates certain crucial choices that works on the unity of consciousness must make. If one identifies the subject of experience with something whose consciousness is necessarily unified, then one cannot offer an account of the objective structure of consciousness. Alternatively, identifying the subject of experience with an animal means forgoing the conceptual connection between being a subject of experience and having a single phenomenal perspective.     

The precuneus and consciousness

This article reviews the rapidly growing literature on the functional anatomy and behavioral correlates of the precuneus, with special reference to imaging neuroscience studies using hamodynamic techniques. The precuneus, along with adjacent areas within the posteromedial parietal cortex, is among the most active cortical regions according to the "default mode" of brain function during the conscious resting state, whereas it selectively deactivates in a number of pathophysiological conditions (ie, sleep, vegetative state, drug-induced anesthesia), and neuropsychiatric disorders (ie, epilepsy, Alzheimer's disease, and schizophrenia) characterized by impaired consciousness. These findings, along with the widespread connectivity pattern, suggest that the precuneus may play a central role in the neural network correlates of consciousness. Specifically, its activity seems to correlate with self-reflection processes, possibly involving mental imagery and episodic/autobiographical memory retrieval.     

The unconscious and consciousness of the memory: A contribution from neuroscience

Abstract

By integrating data from general psychology and perinatal clinical psychology with neuroscience and psychoanalysis, the author discusses the relations between memory and consciousness, the aim being a unitary definition of the concept of unconscious. Nobody has a brain that can be the same as any other person's: the biology of memory lies in neural networks that have been constructed in the brain of that specific person by their experience. From the fetal stage, each brain progressively learns its own individual functions during its relational neuropsychic development. The author underlines how the continuous emotional biological work of the brain, together with a person's entire relational life, produces the construction of the whole functional and individual mindbrain. The whole construction is memory and this is unconscious; indeed it may be the true unconscious. From the continuous silent work of the mindbrain of a person, some forms of conscious level may emerge in his individual's subjectivity: some functioning of mindbrain makes what an individual person can consciously remember. The unconscious is only what appears in some form in an analyst's consciousness, at some specific moment in his relationship with a patient, and which the analyst translates into some form of his verbal interpretation.